The relationship between the outcome of operatively treated calcaneal fractures and institutional fracture load

Background: It has been assumed that outcome after open reduction and internal fixation of displaced intra-articular calcaneal fractures may be affected by the presence of institutional trauma care and the institution's fracture volume. The purpose of this systematic review was to investigate whether a relationship exists between institutional fracture load and the rates of serious infection and subtalar arthrodesis following the treatment of these fractures. Methods: With use of a systematic method, all studies published between 2000 and 2006 describing adult patients undergoing open reduction and internal fixation of a displaced intra-articular fracture of the calcaneus were included. Patients with open fractures and patients undergoing percutaneous procedures were excluded. Institutional fracture load was calculated by dividing the number of calcaneal fractures that were treated operatively by the number of months that were included in the reported studies. A serious deep infection was defined as an infection requiring surgical debridement and hardware removal, reconstruction with a flap, and/or the presence of osteomyelitis. Traumatic subtalar arthritis was considered to be severe when subtalar arthrodesis was required. Numerous confounding factors were also analyzed, and a systematic methodological quality assessment was performed. Results: Of a total of 236 studies, twenty-one were included in the analysis. The total number of fractures included was 1656. The median institutional fracture load was 0.8 fracture per month (95% confidence interval, 0.2 to 4.6 fractures per month). The median infection rate in the studies combined was 5.1% (95% confidence interval, 0.0% to 19.9%). The infection rate increased exponentially with a decreasing fracture load (r(2) = -0.5; p = 0.03). The median rate of subtalar arthrodesis was 2.5% (95% confidence interval, 0.0% to 15.4%). A significant inverse correlation was present between the fracture volume and the subtalar arthrodesis rate (r(2) = -0.7; p = 0.008). These factors were unrelated to the methodological quality. Multivariate analysis identified fracture volume as an independent determinant of the infection rate. Conclusions: A significant relationship between the deep infection rate, traumatic subtalar arthritis, and the fracture load may indicate a need for specialized institutional trauma care to improve outcomes associated with the operative treatment of calcaneal fractures. Level of Evidence: Prognostic Level II. See Instructions to Authors for a complete description of levels of evidence.